6.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Fedor Pchelkin <pchelkin@xxxxxxxxx>
[ Upstream commit 4e3733fd2b0f677faae21cf838a43faf317986d3 ]
There is a slight issue with error handling code inside
nfs42_proc_getxattr(). If page allocating loop fails then we free the
failing page array element which is NULL but __free_page() can't deal with
NULL args.
Found by Linux Verification Center (linuxtesting.org).
Fixes: a1f26739ccdc ("NFSv4.2: improve page handling for GETXATTR")
Signed-off-by: Fedor Pchelkin <pchelkin@xxxxxxxxx>
Reviewed-by: Benjamin Coddington <bcodding@xxxxxxxxxx>
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/nfs/nfs42proc.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/fs/nfs/nfs42proc.c b/fs/nfs/nfs42proc.c
index 93e306bf4430f..5d7e0511f3513 100644
--- a/fs/nfs/nfs42proc.c
+++ b/fs/nfs/nfs42proc.c
@@ -1360,7 +1360,6 @@ ssize_t nfs42_proc_getxattr(struct inode *inode, const char *name,
for (i = 0; i < np; i++) {
pages[i] = alloc_page(GFP_KERNEL);
if (!pages[i]) {
- np = i + 1;
err = -ENOMEM;
goto out;
}
@@ -1384,8 +1383,8 @@ ssize_t nfs42_proc_getxattr(struct inode *inode, const char *name,
} while (exception.retry);
out:
- while (--np >= 0)
- __free_page(pages[np]);
+ while (--i >= 0)
+ __free_page(pages[i]);
kfree(pages);
return err;
--
2.40.1
